Testing device



Nov. 19, 1929. F. E. KREFT 1,736,605

TESTING DEVICE Filed Nov. 27. 1925 NVENTOR ATTORNEY Patented Nov. 19,1929 FRANK E. KREFT, OF CHICAGO, ILLINOIS TESTING DEVICE Application ledNovember 27, 1925. Serial No. 71,790.

10 of the electrical conductivity of electrical appliances, such aslamps, fuses, and the like, and strands or coils of wire and which willembrace the desired features 'of simplicity.

A further object of the invention is the production of a device of thecharacter hereinafter described arranged and adapted to produce a signalascertaining the condition of various electrical appliances. y

Other objects will appear hereinafter.

T he invention consists in the combination and arrangement 0f partshereinafter described.

The invention will be best understood by' 0 arrangement embodied in theinvention.

Referring to the drawing illustrating the preferred form ofconstruction, 10 indicates a box like structure comprising wall members11, a bottom 12 and a removable side Wall 13 all of which when united ina unit provide a compartment 14 for the reception of a battery 15 of anyapproved conventional type. The top wall member 11 has anopening 15formed therein'and carries contact plates 16 and 17 which are secured tothe cover by bending portions thereof to form recesses 18 to receiveadjacent ortions of the top wall as best illustrated inEFig. 2.

The cont-act plate 16 is bent downwardly as at 19 with a portionextending through a slot 20 and then is bent horizontall to bring theportion 21 beneath the top Wal f and partially across the opening-15 insuch manner that a part of the contact plate portion 21 Will be exposedthrough the opening 15. The contact plate 17 has a downwardly bentportion 22 which extends into the opening 15 with its end 23 asubstantial distance from the end of the contact plate portion 21.

The contact plates 16 and 17 are connected in circuit with the battery15 by conductors 2/.1L and 25, there being'an electrical buzzer 26interposed between the battery and conductor plate 16, as bestillustrated in Fig. 6. The construction thus far described is such thata cartridge fuse can be accurately tested by. placing the fuse with itscontact ends in contact with the contact plates 16 and 17 thereby makinga complete circuit between the buzzer and the battery and if the fuse isin usable condition the buzzer will sound a signal but should Vthe fusebe'broken, no sound will be given by the buzzer and this naturally willindicate that the fuse is damaged. The con.- tact plates can also beused to test plug fuses and in such a case the plug is inserted in theopening 15 so as to bring its Contact points in contact With the contactplates to make a complete circuit.

In one of the side Walls 11 a socket 27 is mounted in a convenientmanner and is connected in circuit with the buzzer and battery byconductors 28 and this socket is principally provided for test-ing lampsas well as 'plug fuses.

Provision is also made for testing strands i or coils of wire and thisis accomplished by providing spring clips 30 and 31 which are connectedin the circuit with the buzzer and battery by conductors 32 and it isapparent that when the test is to be made in `this manner the ends ofthe wire are fastened to the clips in the usual manner and if the wireis in one continuous length the buzzer will signal, otherwise if thereis no signal it will indicate that the wire is defective.

It is apparent from the foregoing description and with reference to theaccompanying drawing that I provide a testing device.A for the purposesherein stated and one which will be practical in use as well aseconomical in manufacture.

While I have shown and described the pre- Y erred form of my invention,it is to be understood that various changes and alterations may becarried out during manufacture Without departing from the spirit of theinvention or the scope of the appended claim.

l The invention having been set forth, what I claim as new and usefulis:

In a testing device a wall having an opening formed therein, a contactstrip extending along one side of said wall and having a portionextending into said opening, another contact strip extending along saidside of said Wall including a portion extending through said wall anddisposed to extend along the opposite side thereof across said opening,said portions of said strips disposed adjacent said openingbeing'disposed ,in spaced relation to each other.

In testimony whereof I afiix my signature.

FRANK E. KREFT.

